Lactose, or milk sugar, is a disaccharide carbohydrate which is hydrolyzed during the digestive process to glucose and galactose. This hydrolysis is catalyzed by the enzyme lactase, or beta-galactosidase. Although this enzyme is normally present in the intestinal juices and mucosa, investigations have shown that a significant portion of the population is lactose intolerant or lactase deficient. Consequently, there has been a great demand for a dietary supplement of lactose-hydrolyzing lactase enzymes in lactose intolerant individuals.
Commercially available tablets containing lactase have been observed to have an undesireably short shelf-life. Generally, it is desirable to have a shelf-life beyond about 24 months.
Shelf-life, as used herein for a lactase tablet product, is the time it takes for the lower 95% confidence interval of the product's potentcy plotted versus time to fall below a predetermined lower specification limit. Thus, it can be seen that shelf-life is a function of lactase content uniformity in the tablets and the inherent lactase chemical stability. It is an object of the present invention to formulate a lactase containing tablet composition having improved chemical stability.